The present disclosure relates to an input/output apparatus obtained by extending the function of an input/output terminal used for input/output of an information terminal device.
To receive TV broadcasting by an information terminal device such as a mobile phone, one of the method of providing a dedicated receiving antenna inside the information terminal device and the method of capturing antenna input from an earphone terminal to listen to an audio signal is generally used.
In addition, TV sets can now be easily moved through the miniaturization thereof and there is also a desire to receive TV broadcasting in a room in which there is no antenna receptacle for TV broadcasting such as a kitchen in the home. In such a case, using a power transmission cable as an antenna for TV broadcasting is proposed (see, for example, Patent Literature 1).
According to the technology described in Patent Literature 1 the distance between an inductor for high-frequency cutoff provided on the side of a power supply circuit of a power transmission cable and an inductor for high-frequency cutoff provided on the side of a mobile terminal is set to an integral multiple of the ¼ wavelength of the carrier frequency of received TV broadcasting or the like. Accordingly, TV broadcasting or the like in a wide frequency band can be received.
Also, a receiving apparatus capable of obtaining sufficient antenna characteristics even if a connector is shared when a cable used as an antenna is caused to transmit another signal whose frequency overlaps is proposed by the present inventors (see Patent Literature 2).